That's the case with the proposed rule from the U.S. National Highway Traffic Safety Administration aimed to protect pedestrians and bicycles from being struck by electric and hybrid cars. These cars run silent at slow speeds, putting pedestrians and bicycles in danger because they can't hear the vehicles coming up from behind them. And these silent cars have become particularly dangerous for the blind.

The simple solutions is to require electric and hybrid vehicles to emit detectable sounds when traveling under 18 mph. It is estimated it will cost about $35 per vehicle to add external speakers, which is not much in vehicles that sell for $20,000 or more.

"Our proposal would allow manufacturers the flexibility to design different sounds for different makes and models while still providing an opportunity for pedestrians, bicyclists and the visually impaired to detect and recognize a vehicle and make a decision about whether it is safe to cross the street," NHTSA Administrator David Strickland said in announcing the proposal.

Let's hope the sounds coming from the speakers are not annoying like those high-pitch, grating back-up sounds on everything from industrial fork lifts to golf cars. Let's hope good sense is used in implementing this rule.

It is estimated the quiet-car rule would save 35 lives a year as well as prevent 2,800 injuries, according to a NHTSA statement.

This proposal is not an unnecessary intrusion, not overly expensive or burdensome and it will save lives. NHTSA should finalize the rule sooner rather than later.